For young adult heavy drinkers, higher sensitivity to alcohol’s stimulating and rewarding effects, and lower sensitivity to the sedative effects, predicts continued heavy drinking and future alcohol-related problems. Current alcohol brief intervention (BI) does not address this risk factor. This study assessed the efficacy of BI incorporating personalized alcohol response feedback from smartphone-based assessments of alcohol use and subjective responses during a natural environment drinking episode. Current heavy drinkers (N = 45; 7.8±3.5 past month binge episodes; aged 24.6±2.3 years) were randomized to either: smartphone-based assessments of alcohol use and subjective effects during a natural-environment drinking episode alone (CTL, n = 15), two standard BI sessions (BI-S, n = 10), or two BI sessions incorporating feedback from smartphone assessments of alcohol use and subjective effects during a natural-environment drinking episode (BI-ARF, n = 20). Intervention sessions (28.5±9.1 minutes) were administered via zoom. Drinking behaviors were assessed at baseline, 1- and 3-month follow-up. GEE analysis revealed that all groups showed significant reductions to past month drinking days, binge days, drinks per drinking day, maximum drinks per drinking day, and total drinks consumed (main effect of time, ps ≤ 0.001). However, there were no significant effects of group by time or group interactions (ps > 0.05), suggesting that all groups showed similar significant reductions to these behaviors. Additionally, in all groups, we saw larger reductions than typically seen following BI. To further understand the benefits of personalized alcohol response feedback, future research should be conducted with larger and more diverse samples, including a larger range of alcohol response phenotypes and desire to change drinking behaviors.